<!DOCTYPE html>
<html lang="en">
<!---练习布局--->
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Layout</title>
    <style>
        div{
            border: 1px solid red;  
            height: 200px;
            margin-bottom: 10px;
            position: relative;
                }
    </style>
</head>
<body>
    <div class="head">header</div>
    <div clas="content">
        <span stype="position:absolute;left 20px;top:100px">position</span>
    </div>
    <div class="footer">footer</div>
</body>
</html>